U.S. Pat. No. 4,150,970, Ries et al., issued Apr. 24, 1979, discloses the use of triacontanol to stimulate plant growth. Formulations are prepared by dissolving the triacontanol in organic solvents such as chloroform or benzene and then adding the solution to water, which can also contain an emulsifying agent.
Farm Chemicals, 141:42-46 (1978), discloses that triacontanol significantly increased yields of several crops in limited field testing. However, broad-scale testing is said to be needed in view of the difficulty in finding plant biostimulants consistently effective under practical conditions.
Jones, et al., Planta, 144:277-282 (1979), report that various analogs of triacontanol differing in carbon chain length, position of the hydroxyl group and identity of the terminal functional group all failed to stimulate plant growth, and actually inhibited triacontanol's activity when applied with it. The authors conclude that triacontanol should be free of trace amounts of other long-chain compounds, particularly 1-octacosanol, for effective plant growth stimulation.
U.S. Pat. No. 4,230,485, Ohlrogge, issued Oct. 28, 1980, describes the application of triacontanol to corn plants after tassel initiation to improve yields. The formulations are preferably prepared by dissolving triacontanol in acetone and then mixing the solution with water.
Maugh, Science, 212:33-34 (1981), reports that field testing of triacontanol has proven disappointing and caused many investigators to give up on the compound. Ries is said to attribute most of the problems to inadequate methods of formulation. Welebir is said to think that activity is also related to metal ion concentration and pH.
While triacontanol is known to be useful for stimulating plant growth, it is apparent that there is a continuing need for triacontanol formulations capable of more consistently stimulating growth under practical conditions.